Coolness, or being cool, is an aesthetic of attitude, behavior,
comportment, appearance, and style that is generally admired. Because of the
varied and changing interpretation of what is considered "cool”, as well as
its subjective nature, the word has no single meaning. For most, coolness is
associated with exemplifying composure and self-control. When used in
conversation, it is often as an expression of admiration or approval, and can
be used when referencing both people and items of interest. Although commonly
regarded as slang, "cool" is widely used among disparate social groups and has
endured (in usage) for generations.
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